Can I move phone to a different line on the same account?

I currently have a new(er) phone on my first line that is not upgrade eligible yet. My third line is my daughters. She has an older phone that is unlocked so her line is upgrade eligible. Could I upgrade her line to a new phone so I get promotional pricing, trade-in credit, etc., then switch my existing phone to her line and vice versa, so I end up with the new phone and she gets the phone I have right now? I know my phone has an e-sim. I'm not sure about her phone but I don't think it would matter in this case since her physical phone would no longer be used.